Vacuum Cleaner Filter Assembly

ABSTRACT

A vacuum cleaner filter assembly having a filter frame with a frame sidewall defining an enclosed perimeter. A filter is mounted in the filter frame and has a surface through which air can pass. A deodorizer chamber has a first sidewall connected to a first portion of the frame sidewall, and a second sidewall connected a second portion of the frame sidewall. The deodorizer chamber has a filter-facing portion facing a first portion of the filter, and defines a passage from there to a portion of the chamber not facing the filter. A number of deodorizer pellets are contained in the chamber. The filter assembly has parallel first and second air paths. The first path extends through the first portion of the filter and the chamber. The second path extends through a second portion of the filter that is not covered by the pellet chamber and not through the chamber.

The present application is a continuation of U.S. application Ser. No.12/615,742 filed Nov. 20, 2009, which is a continuation of U.S.application Ser. No. 11/417,167 filed May 4, 2006 and claims priority toprovisional application 60/689,255, filed on Jun. 10, 2005 andprovisional application 60/706,063, filed on Aug. 8, 2005. All four ofthese applications are incorporated herein by reference in theirentirety.

FIELD OF THE INVENTION

The present invention relates to vacuum cleaners, central vacuumcleaners, extraction cleaning devices, and other cleaning applianceshaving chemical neutralizing features.

BACKGROUND OF THE INVENTION

Many types of cleaning devices are available for commercial and consumercleaning needs. For example, conventional vacuums are often used forgeneral floor cleaning, central vacuum systems have been developed for aconvenient means of general floor cleaning, various types of extractioncleaners have been developed to provide deeper or more problem-specificcarpet and upholstery cleaning, and cleaning wands having dry ormoistened disposable wipes are used for quickly cleaning hard surfaces.

A common problem among these and other cleaning appliances is that theyoften pick up or develop odors from the substances that they clean offthe floor. Such odors can make it undesirable to operate or clean theappliance, or give the perception that the cleaning appliance is notcleaning effectively, and result in customer dissatisfaction with thedevice. These odors may also present a perceived health risk.

Various attempts have been made to address the accumulation of odors incleaning appliances. For example, U.S. Pat. No. 5,461,751, which isincorporated herein by reference, discloses a vacuum cleaner having acedar insert in the vacuum bag that acts as an air freshener andpesticide. In another device, shown in International Patent PublicationWO 01/08543 A1, an adsorbent material such as activated carbon isintroduced into a vacuum dust filter bag. While the foregoingdevelopments have been useful for controlling or masking odors, theyhave not conclusively solved the problem of lingering odors in cleaningappliances and preventing odors on surfaces being cleaned.

In view of these and other problems, there remains a need to provideimproved methods and apparatuses for controlling odors in cleaningappliances.

SUMMARY OF THE INVENTION

In one aspect, there is provided a vacuum cleaner filter assembly havinga filter frame, a filter, and a deodorizer chamber. The filter frame hasan enclosed perimeter defined by one or more frame side walls. Thefilter is mounted in the filter frame, and has a working surface areathrough which air can pass during use. The deodorizer chamber has afirst chamber side wall connected to a first portion of the one or moreframe side walls, and a second chamber side wall connected a secondportion of the one or more frame side walls. The deodorizer chamber alsohas at least one filter-facing portion facing a first portion of thefilter, and the chamber defines a passage from the at least onefilter-facing portion to a portion of the chamber not facing the filter.At least one deodorant, such as one or more pellets of sodiumbicarbonate or other deodorizing material, is contained in thedeodorizer chamber. The filter assembly provides parallel first andsecond air flow paths. The first air flow path extends through the firstportion of the filter and the deodorizer chamber, and the second airflow path extends through a second portion of the filter that is notcovered by the deodorizer chamber and does not extend through thedeodorizer chamber.

In one aspect, there is provided a vacuum cleaner filter assembly havinga rectangular filter frame, a filter, and a pellet chamber. The filterframe has first and second frame side walls spaced from each other by afilter frame width, and first and second frame end walls joining thefirst and second frame side walls and spaced from each other by a filterframe length. The filter is mounted in the filter frame, and has aworking surface area through which air can pass during use. At least aportion of the filter has a plurality of pleats. The pellet chamber hasa first chamber side wall connected to the first frame side wall, and asecond chamber side wall connected to the second frame side wall. Thepellet chamber also has a rectangular filter-facing portion facing afirst portion of the filter, and the pellet chamber defines a passagefrom the filter-facing portion to a portion of the pellet chamber notfacing the filter. A number of discrete deodorizer pellets are containedin the pellet chamber. The deodorizer pellets include an odorneutralizing substance. The filter assembly provides parallel first andsecond air flow paths. The first air flow path extends through the firstportion of the filter and the pellet chamber, and the second air flowpath extends through a second portion of the filter that is not coveredby the pellet chamber and does not extend through the pellet chamber.The entire filter assembly is connected as a single replaceableoperative unit. The filter assembly is adapted to filter all of a totalair flow passing through it, and deodorize only a portion of the totalair flow passing through it.

In one aspect, there is provided a vacuum cleaner filter assembly havinga filter frame, at least one air-permeable filter, and an air-permeabledeodorizer chamber. The filter frame has a number of frame members,including two side frame members and two end frame members. The filterframe defines an outer boundary of an air passage through which air canpass during use. The filter is mounted to the filter frame, and extendsbetween the frame members across substantially the entire air passage.At least a portion of the at least one filter is pleated. The deodorizerchamber extends between and is attached to two at least two of the framemembers, and the deodorizer chamber has a filter-facing portion. Aneffective amount of deodorizer is contained in the deodorizer chamber.The filter assembly provides first and second air flow paths, in whichthe first air flow path extends through a first portion of the at leastone filter and through the deodorizer chamber, and the second air flowpath extends through a second portion of the at least one filter that isnot covered by the chamber.

Other uses and variations on the foregoing will be apparent to one ofordinary skill in the art after studying the present disclosure andpracticing the invention described herein.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a first set of embodiments of the present invention shown inconjunction with a bag vacuum cleaner.

FIG. 2A illustrates schematic views of an exemplary bagless vacuumcleaner of the present invention showing the air flow path therein.

FIG. 2B is a first set of embodiments of the present invention shown inconjunction with the exemplary bagless vacuum cleaner of FIG. 2A.

FIG. 2C is a second set of embodiments of the present invention shown inconjunction with the exemplary bagless vacuum cleaner of FIG. 2A.

FIG. 3A is a first embodiment of the invention shown for use with avacuum cleaner filter.

FIG. 3B is a second embodiment of the invention shown for use with avacuum cleaner filter.

FIG. 3C is a third set of embodiments of the invention shown for usewith a vacuum cleaner filter.

FIG. 4A is an embodiment of the present invention shown in conjunctionwith an upright wet extractor.

FIG. 4B is an embodiment of the present invention shown in conjunctionwith a canister wet extractor.

FIG. 4C is an embodiment of a pass-through sodium bicarbonate reservoirof the present invention.

FIG. 4D is an embodiment of a sodium bicarbonate reservoir of thepresent invention.

FIG. 4E is an embodiment of the present invention comprising a wetextractor having a dry deposition system associated therewith.

FIG. 4F is a schematic cutaway side view of the embodiment of FIG. 4E.

FIG. 5A is an embodiment of the present invention shown in conjunctionwith a cleaning wand.

FIG. 5B is two embodiments of sodium bicarbonate cleaning pads that maybe used with the embodiment of FIG. 5A.

FIG. 5C illustrates alternative variations of the embodiment of FIG. 5A.

FIG. 6 is an embodiment of a sodium bicarbonate deposition system of thepresent invention.

FIG. 7A is an embodiment of a sodium bicarbonate deposition system ofthe present invention as attached to a cyclonic-type dustcup.

FIG. 7B is top, plan view of the embodiment depicted in FIG. 7A.

FIG. 7C is a cross-sectional view of the embodiment depicted in FIG. 7B,shown along line I-I thereof.

FIG. 7D is top, plan view of one embodiment of a sodium bicarbonatedeposition system.

FIG. 7E is a cross-sectional view of the embodiment depicted in FIG. 7D,shown along line II-II thereof.

FIG. 7F illustrates another embodiment of a sodium bicarbonatedeposition system.

FIG. 7G is a cross-sectional view of the embodiment depicted in FIG. 7F,shown along line III-III thereof.

FIG. 8 is an embodiment of a temperature sensitive sodium bicarbonatedeposition system of the present invention.

FIG. 9A illustrates an embodiment of a chemically-impregnateddeodorizing sheet of the present invention and an accompanyingcontainer.

FIG. 9B illustrates an embodiment of a chemically-impregnateddeodorizing sheet of the present invention and another form ofpackaging.

FIG. 9C is an embodiment of a chemically-impregnated deodorizing sheetof the present invention as used in a cyclonic dustcup container.

FIG. 10A is an embodiment of a chemically-impregnated deodorizing sheetof the present invention pre-installed in a conventional bag-typefilter.

FIG. 10B is a cross-sectional view of the embodiment of FIG. 10A, shownalong line IV-IV thereof.

FIG. 10C is an embodiment of a chemically-impregnated deodorizing sheetof the present invention pre-installed in a conventional bag-typefilter.

FIG. 10D is a cross-sectional view of the embodiment of FIG. 10C, shownalong line V-V thereof.

FIG. 10E is an embodiment of a chemically-impregnated deodorizing sheetof the present invention pre-installed in a conventional bag-typefilter.

FIG. 10F is a cross-sectional view of the embodiment of FIG. 10E, shownalong line VI-VI thereof.

FIG. 10G is an embodiment of a chemically-impregnated deodorizing sheetof the present invention pre-installed in a conventional bag-typefilter.

FIG. 10H is a cross-sectional view of the embodiment of FIG. 10G, shownalong line VII-VII thereof.

FIG. 11A is an embodiment of a method of manufacturing one embodiment ofa chemically-impregnated deodorizing sheet.

FIG. 11B illustrates the chemically-impregnated sheet made from theprocess depicted in FIG. 11A.

FIG. 12A is another embodiment of a method of manufacturing anotherembodiment of a chemically-impregnated deodorizing sheet.

FIG. 12B illustrates the chemically-impregnated sheet made from theprocess depicted in FIG. 12A.

FIG. 13A is an embodiment of a disk-shaped chemically-impregnatedarticle of the present invention.

FIG. 13B illustrates the process used to create the embodiment of FIG.13A.

FIG. 13C is a variation of the embodiment of FIG. 13A.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention provides methods and apparatuses for neutralizingodors in cleaning appliances, such as vacuum cleaners, central vacuumsystems, extractors, and cleaning wands. The methods and apparatusespreferably use sodium bicarbonate, a non-toxic and non-irritatingsubstance having the chemical formula NaHCO₃, and often referred to asbaking soda. Sodium bicarbonate is a known compound, and is generallyprovided as a white, powdered substance, but it is also known to form itinto a solid form or a liquid slurry. It is in widespread use as acooking additive, for acid reduction, and as a mild abrasive forcleaning. Sodium bicarbonate also acts as a deodorizer by neutralizingthe acidic or basic components of odors and turning them intonon-volatile salts. Various commercial products have been developed touse sodium bicarbonate in refrigerators and on carpets to reduce odorsproduced by foods, pets, smoke, and other sources. An example of aproduct that is used for deodorizing carpets is sold under the name ARM& HAMMER CARPET AND ROOM DEODORIZER, which is available from Church &Dwight Co., Inc., of Princeton, N.J. This product is generally depositedby hand on a carpet, and removed with a conventional vacuum cleaner.

Referring to the included Figures, in a first embodiment, the presentinvention provides a sodium bicarbonate chemical neutralizer that isused in conjunction with a vacuum cleaner 100 having a bag-type dirtfilter 102. Numerous variations of this embodiment are envisioned, andfor ease of illustration a number of these variations are shown on asingle vacuum cleaner 100 in FIG. 1. It is believed that any one of thevarious employments of sodium bicarbonate neutralizers shown in FIG. 1may be sufficient to obtain favorable odor neutralization, and thereforethe invention contemplates and encompasses the use of any combination ofone or more of these variations with a bag filter-type vacuum cleaner.

The vacuum cleaner of FIG. 1 is generally of conventional construction,and includes a floor-contacting base 104 to which an upright rearhousing 106 is pivotally attached. The rear housing 106 can bepositioned in an upright resting position and leaned back for use inguiding the base 104 across the surface being cleaned, as known in theart. The base includes an inlet nozzle 108, which may have a rotatableagitator (not shown) mounted therein.

The nozzle 108 is connected to the filter bag 102 by an inlet conduit110. A typical inlet conduit 110 comprises a series of rigid and/orflexible tubes. All or a portion or the conduit 110 may be transparentto help locate clogs, and a portion of the conduit 110 may be removableto assist with cleaning clogs therefrom. An example of a conduit 110having a transparent, removable portion is shown in U.S. Pat. No.5,991,791, which is incorporated herein by reference. The inlet conduit110 may be detachable from the base 104 for use as an above-floorcleaning hose, or may include a valve that cuts off airflow from theinlet 108 and redirects the airflow to a separate above-floor cleaninghose. Such devices are known in the art.

A conventional fan and motor assembly 101 is used to generate a vacuumto draw dirt-laden air into the nozzle 108, through the conduit 110, andinto the dust bag 102. The fan may be fluidly located at some point inthe conduit 110 to convey the dirt-laden air to the filter bag 102 underpositive pressure, or may be located downstream of the filter bag 102 todraw dirt-laden air into the filter bag 102 under a vacuum. The secondalternative is shown in FIG. 1. Additional filters may also be providedin the conduit 110 or at locations downstream of the filter bag 102 toprovide additional dirt filtration and air cleaning.

The filter bag 102 is located within a bag chamber 112 on the rearhousing 106, which is covered by a suitable lid 114. The chamber 112 andlid 114 may optionally be replaced by an air-permeable fabric cover asmay be desired when the fan is positioned to convey the air into thefilter bag 102 under pressure. The filter bag 102 is releasably mountedto the end of the conduit 110 by a mounting tube 115 that fits into acorresponding mounting flange 118 on the filter bag 102. This type ofbag mounting arrangement is known in the art, and shown, for example, inU.S. Pat. Nos. 4,119,414; 6,217,641; and 6,484,352, which areincorporated herein by reference. A lock-out device (not shown) may beprovided to prevent operation of the vacuum cleaner 100 or closure ofthe lid 114 without the presence of the filter bag 102.

Other features and accessories of the vacuum cleaner 100 will beunderstood by those of ordinary skill in the art, and the invention isnot intended to be limited to any particular construction. Non-limitingexamples of typical vacuum cleaners and features that can be used withthe present invention are shown in U.S. Pat. Nos. 4,376,322; 5,309,361;6,122,796; and 6,308,374, which are incorporated herein by reference.Furthermore, while the embodiments of FIG. 1 are described withreference to a conventional upright vacuum cleaner, they may be used ingenerally the same manner in vacuums having different configurations,such as canister or stick-type vacuums, central vacuums, and the like.Non-limiting examples of such vacuums include those shown in U.S. Pat.Nos. 5,701,631 and 5,813,085, which are incorporated herein byreference. The changes to the designs set forth above required to usethe invention in these different vacuum configurations will be apparentto those of ordinary skill in the art.

The vacuum cleaner 100 of FIG. 1 is provided with various sodiumbicarbonate neutralizing structures. A first such structure is in theform of an air-pervious bag or sachet 120 filled with sodiumbicarbonate. The sachet 120 may be located within the filter bag 102, onthe outside of the filter bag 102, or within the filter bag compartment112. The sachet 120 may also be located on the interior or exterior ofthe filter bag fabric cover, if one is used. In this embodiment, thesachet 120 may be provided as a separate device as an aftermarketodor-neutralizing additive that can be used with any vacuum cleaner. Inthis case, the sachet 120 may be simply placed in the desired location,or may be provided with an adhesive backing or clips to hold it inplace. The sachet 120 may alternatively be sewn into or formed as partof the filter bag 102. For example, when formed as part of the filterbag, the sachet 120 may be formed by creating a fold in the filter bagmaterial, filling the fold with sodium bicarbonate, and sewing orbonding the fold shut so that the sodium bicarbonate is capturedtherein. Other examples of such embodiments are described elsewhereherein.

In another embodiment, a slurry of sodium bicarbonate is printed orpainted onto the filter bag material before or after it is formed intothe filter bag 102. The sodium bicarbonate may also be provided in apowdered form that is captured between layers of the filter bag 102. Aparticular advantage these embodiments is that the supply of sodiumbicarbonate is renewed whenever the filter bag 102 is replaced. Ineither of these embodiments, it is believed that the amount of sodiumbicarbonate can be adjusted so that it provides odor neutralization,while not unduly reducing the permeability of the filter bag 102. Forexample, if the sodium bicarbonate is painted on the filter bag 102,this may be done so in stripes or other patterns that leave portions ofthe filter bag 102 in their original, porous state. When capturing thesodium bicarbonate between the layers of the filter bag, the basisweight of the sodium bicarbonate can be adjusted to minimize anydetrimental effects on the bag's porosity.

In another embodiment, an odor neutralizing structure of sodiumbicarbonate is formed as a rigid sleeve 122 that fits within the inletconduit 110. In this embodiment, the conduit 110 can be selectivelyopened or detached to allow the sleeve 122 to be inserted therein. Asthe incoming dirt-laden air passes through the conduit 110 and thesleeve 122, the sleeve 122 gradually erodes, thus providing controlleddistribution of the sodium bicarbonate into the filter bag 102, where itcan react with the collected matter to neutralize offensive odors. Thesleeve 122 may be located within a transparent, removable portion of theconduit 123 to assist the user in determining when the sleeve 122 is ator near the end of its useful life.

In a variation of this embodiment, the sodium bicarbonate my be adheredto the interior walls of a portion of the conduit 110, rather thanprovided as a replaceable sleeve 122. In this embodiment, the portion ofthe conduit 110 to which the sodium bicarbonate is adhered may beprovided as a replacement part for use when the original supply is fullyeroded, or adhesive-backed inserts may be provided as replacements.

The sodium bicarbonate may also be molded into a rigid insert 116 thatfits over or within the bag mounting tube 115. In this embodiment, theinsert 116 is installed on or in the mounting tube 115 whenever a newbag is placed in the device, or whenever the insert becomes sufficientlyeroded. The sodium bicarbonate may also be formed as a tube that servesas the mounting tube 115 itself. An advantage of this construction isthat the consumer is not able to mount the filter bag 102 and operatethe device without the sodium bicarbonate form being present.

Referring now to FIGS. 2A-2C, the present invention also may be usedwith bagless vacuums, such as those that use a dust cup, rather than afilter bag. Non-limiting examples of various other canister and uprightbagless vacuums that may be used with the present invention includethose shown in U.S. Pat. Nos. 4,665,582; 6,168,641; 6,311,366;6,502,277; and 6,863,702, which are incorporated herein by reference.FIG. 2A illustrates side and top cutaway views of a typical uprightbagless vacuum cleaner that may use the present invention. FIGS. 2B and2C illustrate two sets of embodiments of the present invention that maybe used with the vacuum cleaner of FIG. 2A, or other vacuums, such asstick or canister vacuums. A number of variations of this embodiment areshown on a single bagless dust cup in FIGS. 2B and 2C, but any one ormore of the various employments of sodium bicarbonate neutralizers shownin FIGS. 2B and 2C may be used with a bagless vacuum cleaner on its ownor in other combinations.

The bagless dustcup 200 of FIG. 2A comprises a dirt receptacle 202 towhich a lid 204 is attached by bayonet fittings 206, threadedengagement, compression fitting, or other known attachment devices. Thedirt receptacle 202 preferably is made of a transparent plasticmaterial, or with a transparent window, so that its contents can bereadily examined. The dirt receptacle 202 has a dirty air inlet passage208 that opens into the dirt receptacle 202 at an inlet opening 210. Airis drawn into the dirty air inlet passage 208 through an inlet nozzle211 in a base assembly 213 by a vacuum motor 212. As the incomingdirt-laden air enters the dirt receptacle 202, it is forced into aswirling, centrifuging motion by a deflector plate 214 located adjacentthe opening 210. This centrifuging motion separates larger particlesfrom the air in the manner of conventional cyclonic separators, and thepartially-cleaned air exits the dirt receptacle 202 through a pleatedfilter 216. The exiting air passes through an outlet passage 218 in thelid 204, and then to the vacuum motor 212. Alternatively, the outletpassage 218 may extend downward and exit through the bottom of the dirtcup 200, as known in the art.

Sodium bicarbonate odor neutralizers can be integrated into the dirt cup200 in a number of ways, but are preferably provided as sacrificialsolid forms of sodium bicarbonate that are located in the airstream suchthat they are gradually eroded by the air flowing through the device, oras sodium bicarbonate-impregnated filter elements located within thedirt cup 200. In a first embodiment, shown in FIG. 2B, the sodiumbicarbonate is molded to form (or be attached to) the inlet deflectorplate 214. In this embodiment, the incoming airstream strikes thedeflector plate 214, causing gradual erosion of the solid sodiumbicarbonate. The freed sodium bicarbonate is expected to mix with thecontents of the airstream in a uniform manner, and thereby chemicallyneutralize odors of the material in the airstream. The remaining solidsodium bicarbonate and the eroded sodium bicarbonate also helpneutralize odors present in the dustcup 200 when the device is not inuse. In this embodiment, the sodium bicarbonate deflector plate 214 (orthe sodium bicarbonate attachment thereto) can be replaced periodicallyas it erodes.

In another embodiment, also shown in FIG. 2B, the pleated filter 216 mayinclude a reverse airflow deflector 220 that is attached to the bottomof the filter 216. This reverse flow deflector 220 may be formed of asolid sodium bicarbonate material that gradually erodes and neutralizesodors in the dustcup, as described above. In still another embodiment inFIG. 2B, an insert 222 made of a solid sodium bicarbonate material maybe provided in the filter 216. This insert 222 may take the form of asimple sleeve or pellet(s). The insert 222 may also be shaped to createa tortuous or spiraling airflow path that causes the air exiting thefilter to pass across its surface to thereby release sodium bicarbonatefrom the insert 222. For example, the shown insert 222 is shown havingan auger-like shape that forces the air to cross a relatively largesodium bicarbonate surface area before exiting the device. The insert 22may alternatively comprise a powder in an air-permeable sachet, asdescribed previously herein, a sodium bicarbonate impregnated airpermeable sheet, as described later herein, or other device.

The pleated filter 216 of the embodiment of FIG. 2B may also be providedwith a pattern of sodium bicarbonate, which can be impregnated into thefilter material itself, or painted or printed onto the filter mediumbefore or after it is formed into a pleated filter 216. In the shownembodiment, two sodium bicarbonate strips 232 are applied to the pleatedfilter 216. The amount of sodium bicarbonate applied to the filter inthis manner preferably has sufficient mass to provide odorneutralization in the dirt receptacle 202, but is not so great that itunduly reduces the efficiency of the filtration process. Blockage of upto 20% or more may be allowable, depending on the total filter area andthe filtration requirements of the vacuum cleaner.

Other embodiments of the invention do not include a pleated filter 216.For example, the filter 216 may be replaced by a conical or cylindricalperforated or screen cyclone center 224, as shown in FIG. 2C. In thisembodiment, a solid sodium bicarbonate insert 226 may be provided withinthe cyclone insert so that air entering the cyclone insert strikes theinsert 226. Ribs 228 on the insert 226, or more preferably on the innersurface of the cyclone center 224 (not shown), keep the sodiumbicarbonate insert 226 from blocking airflow through the cyclone center224. The cyclone center 224 may also have a solid or perforated sodiumbicarbonate sleeve 230 positioned on its exterior surface to contact theair swirling around the cyclone center 224.

Other variations on sacrificial, renewable sodium bicarbonate insertsand other forms will be apparent to those of ordinary skill in the artin view of the present disclosure and with practice of the invention.

Referring now to FIGS. 3A-3C, the present invention also includes acleaning device filter having a sodium bicarbonate element or elementsintegrated into the filter. The sodium bicarbonate is held in proximityto the filter medium, but is located so that it does not unduly inhibitthe airflow through the filter medium. The filter may be used as a dirtcup filter, a pre- or post-motor filter, or for any other purpose, andmay comprise a pleated filter, planar filter, foam filter, or any othertype of airflow filter, and may be made of any material, such asnon-woven materials, natural or synthetic fibers, foams, and the like.The filter may have any particle separation efficiency grade, such asHEPA (High Efficiency Particulate Air), ULPA (Ultra Low Penetration,Air), or SULPA (Super Ultra Low Penetration, Air), or may not have aspecific filtration grade.

In a first embodiment, shown in FIG. 3A, the present invention providesa filter 300 comprising a frame 302 that holds a pleated or foam filter304 and has a chamber 305 to hold a supply of solid sodium bicarbonate306. The frame 302 is arranged such that the air flow passes through thefilter medium 304, and at least a portion of the airflow also passesthrough the chamber 305 so that it is treated by the sodium bicarbonate306, such as shown in the side cross-sectional view portion of FIG. 3A.The sodium bicarbonate 306 is preferably provided as tablets or spheresthat allow a significant amount of airflow therethrough. The chamber 305can optionally extend across the entire filter medium 304, and mayinclude an air-permeable cover (not shown) to hold the sodiumbicarbonate in place. The filter medium 304 may be washable, in whichcase the user would either remove the sodium bicarbonate before washingthe filter medium 304, and replace it afterwards, or put a new supply ofsodium bicarbonate in the chamber 305 after each wash.

In another embodiment, shown in FIG. 3B, the invention provides a filter308 having a generally conventional frame 310 that holds the filtermedium 312. The frame 310 also includes a hinged door 314 that can bepivoted to cover the filter medium 312. The door 314 includes a numberof openings 316 through which air can pass to the filter medium 312.Some or all of the openings 316 are provided with sodium bicarbonatetablets 318 that fit in the openings 316 without entirely blocking them.This can be accomplished in any number of ways, but is preferably doneby providing each opening 316 with a number of flex arms 320 into whicha projecting pin 322 on the sodium bicarbonate tablet 318 frictionallyfits. Standoff ribs 324 on the tablet 318 prevent the tablet 318 fromfitting flush against the door 314 and blocking the openings 316. Whenthe door 314 is closed, the tablets 318 are captured against the filtermedium 312. In this embodiment, the tablets 318, door 314, or the entirefilter 308 may be replaceable. While the door 314 is shown beingpivotable on hinges, it will be appreciated that it may simply comprisea separate part that is placed adjacent the filter medium 312 or snappedin place, or may be fixed in place. In variations of this embodiment,the sodium bicarbonate may alternatively be adapted to clip ontoconventional filters by friction fit, which may be accomplished byproviding a sodium bicarbonate tablet with a slot that fits over afilter pleat and is held in place by friction and/or gripping teethformed in the slot. The sodium bicarbonate may also be provide astablets that have pins or other devices that allow them to be attachedto any filter.

In another embodiment, shown in FIG. 3C, a sacrificial perforated sodiumbicarbonate plate 326 is provided. The plate 326 has a number of holes328 to allow air to pass therethrough, and is shaped such that it fitsagainst a conventional filter or elsewhere in the cleaning device'sairflow path. The sodium bicarbonate plate 326 may be captured in placewhen it is installed between the filter, the cleaner housing and thefilter cover, or may be provided with snaps or other fasteners to holdit in place. While the holes 328 are shown as being relatively large,the sodium bicarbonate plate 326 may instead be formed with small holesor such that it appears solid but actually has a high air permeabilityto allow the air to pass through the plate itself.

In another embodiment of FIG. 3C, one or more solid sodium bicarbonateforms 330 or powder sachets are positioned in a frame 332 that isadapted to fit adjacent a conventional filter. The forms 330 are heldgenerally in place on or by a mesh web 334 within the frame 332. Eachform 330 may be adhered to the mesh web 334, or they may be captured inplace between two meshes. The mesh is preferably large enough that itdoes not inhibit the airflow to the filter, but may be made of a filtermaterial.

In still another embodiment of FIG. 3C, sodium bicarbonate can beadhered to, painted, or printed on a conventional filter medium 336 ofany type. In this embodiment, the sodium bicarbonate is printed on thefilter medium 336 in strips 338 or other patterns so that it does notunduly inhibit the airflow through the filter.

In still another embodiment, of FIG. 3C, the sodium bicarbonate isapplied to a sheet 340 that is located adjacent to a conventional filter342, such as a pleated or foam filter. A suitable deodorizing sheet 340and methods for making such a sheet are described in detail herein withreference to FIGS. 10A-12B. In this embodiment, the sheet 340 ispreferably adhered to the filter by a pattern of air-impervious adhesivethat covers about 5% to about 20% of the sheet's surface area, but othertypes of attachment may be used. Furthermore, it is also envisioned thatthe sheet 340 may be captured in place against the filter 342 by beinginstalled within a frame 344 that holds the filter 342, or the sheet 340may be directly attached to the frame 344. In addition, the sheet 340may be provided as a separate part that may be placed against the filter342 when it is installed in a vacuum cleaner. While the sheet 340 isshown having approximately the same planar area as the filter 342, itmay be larger or smaller, as needed. In addition, while the filter inFIG. 3C is shown as being flat (or somewhat curved, which would stillgenerally be considered a flat filter), it mat instead be cylindrical,frustoconical, conical, or have any other three-dimensional shape asneeded for a particular vacuum application.

Referring now to FIGS. 4A-4F, the present invention also provides asodium bicarbonate chemical neutralizer in conjunction with wetextraction cleaning machines. Non-limiting examples of wet extractorsand features thereof that may be used with the present invention areshown in U.S. Pat. Nos. 4,910,828 and 5,933,912, which are incorporatedherein by reference. FIG. 4A shows an upright wet extractor 400 and FIG.4B shows a portable canister wet extractor 402 that may be used with thepresent invention.

The upright wet extractor 400 of FIG. 4A comprises a floor-contactingbase 404 to which an upright handle 406 is pivotally attached and usedto guide the base 404 on the carpet or other surface to be cleaned. Theupright extractor 400 has a supply tank 408 in which a supply of cleanwater or detergent is contained, and a recovery tank 410 for holdingdirt and dirty fluid recovered from the carpet. The extractor 400 mayalso include a separate auxiliary tank 412 that contains a separatesupply of detergent for mixing with the fluid from the supply tank 408.The base 404 also includes one or more sprayers (not shown) or otherfluid deposition devices, and an inlet nozzle 414 that is directeddownwards to the carpet. A fluid pump or gravity-feed system conveys thecleaning fluid from the supply tank 408 and auxiliary tank 412, if oneis used, to the sprayers. A vacuum fan (not shown) is used to generate aworking air flow into the inlet nozzle 414 and through the recovery tank410, as known in the art. The various working parts of the wetextractors 400, 402 are generally known in the art, and shown in U.S.Pat. Nos. 4,910,828 and 5,933,912, and elsewhere.

The portable extractor 402 of FIG. 4B is similar to the uprightextractor 400, and has its own supply tank 428, recovery tank 430,suction fan (not shown), and fluid pumping system (not shown). Theportable extractor 402 uses a hand-held cleaning tool 432, which isattached to the extractor base by a flexible vacuum hose 434. The vacuumhose 434 also includes a fluid supply hose (not shown), which can beexternal or internal to the hose 434. The cleaning tool 432 has one ormore sprayers (not shown) and an inlet nozzle 436 to recover thedeposited fluid and dirt entrained therein.

Sodium bicarbonate 403 can be introduced into either wet extractor 400,402 in a number of ways. In a first embodiment of the invention, thesodium bicarbonate 403 is placed directly in the supply tank 408 in apowder 450, tablet 452, or liquid 454 form, and distributed on thecarpet with the cleaning fluid. In another embodiment, the sodiumbicarbonate is placed in the separate auxiliary tank 412, and mixed withclean water from the supply tank 408. In this embodiment, the sodiumbicarbonate may be used alone as a liquid concentrate, or may be mixedwith detergents or other chemicals in the auxiliary tank 412. Themixture ratio of the sodium bicarbonate and the clean water may be fixedor variable, and any type of metering system may be used to control themixture of sodium bicarbonate concentrate from the auxiliary tank 412with the clean water from the supply tank 408. Such metering systems areknown in the art, and shown, for example, in U.S. Pat. Nos. 4,570,856and 6,286,180, which are incorporated by reference herein.

In another embodiment, the sodium bicarbonate is located in one or morepass-through reservoirs located in the fluid flow path between thesupply tank 408 and the sprayer(s). For example, FIG. 4C illustrates asodium bicarbonate reservoir 416 for the upright wet extractor 400 thatis located along a fluid hose 418 that leads from the supply tank 408 toa spray nozzle 420. This configuration is also used with the portableextractor 402, in which a pass-through reservoir 438 is located in thecleaning tool 432. Either reservoir 416, 438 may be replaced by a liquidconcentrate reservoir that introduces a metered supply of concentratedliquid sodium bicarbonate into the fluid from the supply tank 428, asdescribed above, and such a liquid concentrate reservoir and the shownreservoirs of 416, 438 may be selectively removable from the device.

The pass-through reservoir 416 of FIG. 4C has a removable lid 422 sothat it can be refilled when necessary. The lid 422 is preferablyreadily accessible by the operator, either by being located on the outersurface of the device, or by being accessed upon removal of the supplytank 408 or other removable parts. While the reservoir 416 is shownadjacent the sprayer 420, it may be located elsewhere in the fluid flowpath, and may also be formed integrally with the sprayer 420, the supplytank 408, the pump housing (not shown) or other parts of the device. Thewet extractor 400, 402 may also include one or more other sprayers thatdo not have pass-through reservoirs, and a fluid bypass system (such asvalves or separate fluid pumps) that allows the user to select whichsprayers are used. With this arrangement, the operator can stop andstart the use of the sodium bicarbonate by selectively activating thesprayer(s) having the pass-through reservoirs 416 associated therewith.

In a variation of the foregoing embodiment shown in FIG. 4D, thepass-through reservoir 416 may comprise a reservoir 424 that is locatedadjacent the exit of the extractor's spray nozzles 426 to receive all ora portion of the sprayed fluid. In this embodiment, the reservoir 424may comprise a tray into which the sodium bicarbonate is placed to mixwith the sprayed or poured fluid. Such a reservoir 424 may also bereplaced by a solid bar of sodium bicarbonate that is struck by theemerging spray and slowly eroded and deposited on the surface beingcleaned.

In any of the forgoing embodiments in which the sodium bicarbonate isplaced in a reservoir, the reservoir may be provided with a filter toprevent large sodium bicarbonate particles from clogging the wetextractor's fluid deposition system.

In another embodiment of the invention shown in FIGS. 4E and 4F, thesodium bicarbonate is provided in a powder form that is deposited on thesurface being cleaned, rather than being supplied with the cleaningfluid. In this embodiment, the extractor base 404 (or cleaning tool 432)includes a sodium bicarbonate receptacle 440 located on the front of thebase 404. The receptacle 440 has a manually or automatically controlleddeposition slot that opens to allow sodium bicarbonate to fall onto thesurface being cleaned. Such powder deposition systems are known in theart. The powdered sodium bicarbonate is then worked into the surface 442by an agitator brush 444, which can help loosen dirt and debris andgently abrade the surface being cleaned. Fluid may be simultaneously orsubsequently deposited on the surface 442 by one or more sprayers 446,and the fluid, dirt, and sodium bicarbonate are removed by the suctioninlet nozzle 448.

The foregoing examples are not intended to limit the invention, andother variations on using sodium bicarbonate with wet extractors will beappreciated in light of the present disclosure and with practice of theinvention. The use of sodium bicarbonate with extractors in the mannersdescribed above is expected to provide numerous benefits. For example,it is expected to provide additional cleaning benefits by virtue of themildly abrasive nature of the sodium bicarbonate. It is also expected toenhance odor neutralization in the surface being cleaned by leaving aslight residue of sodium bicarbonate thereon. The recovered sodiumbicarbonate is also expected to reduce odors in the supply tanks, aswell as in the inlet nozzle 414, 436, vacuum hose 434, and recovery tank410, 430. This can be particularly advantageous when the extractor isused frequently, or is used infrequently and not thoroughly cleanedafter every use. The sodium bicarbonate should also reduce odors in thesink or other receptacle into which the recovery tank may be emptied.

Referring now to FIGS. 5A-5C, the present invention also provides asodium bicarbonate chemical neutralizer in conjunction with a floorcleaning wand 500. The cleaning wand 500 comprises a handle 502 having acleaning head 504 pivotally attached thereto. Such cleaning wands areknown in the art, and typically used in conjunction with a disposabledry or pre-moistened cleaning pad that fits on the bottom of thecleaning head 504.

In a first variation of the present invention, shown in FIG. 5A, thecleaning wand 500 has a fluid reservoir 506 that is attached to thecleaning head 504 by a hose 508. A suitable control valve (not shown) isprovided so that an operator can stop or control the fluid flow from thereservoir 506 to the head 504, preferably by a controller 510 located inthe grip portion of the handle 502. The hose 508 enters a manifold 512on the cleaning head 504, which distributes the fluid across the widthof the cleaning head 504.

In this embodiment, the device is provided with a cleaning pad 514,which is retained on the cleaning head 504 by any suitable device, suchas strings 516, clips or other devices. The cleaning pad 514 has amultilayered construction having a first layer 514 a, a second layer 514b, and a third layer 514 c sandwiched between the first and secondlayers. The first and second layers 514 a, 514 b preferably comprisefabric, sponge or non-woven materials. The third layer preferablycomprises a layer of sodium bicarbonate in solid or powder form.

The cleaning pad 514 may be provided in any suitable form. For example,as shown in FIG. 5B, the pad 514 may be provided as a pre-moistened padthat is impregnated with a sodium bicarbonate liquid. In thisembodiment, each pad 514 can be conveniently packages individually insealed pouches 524, which are collected in a box 526. The pads 514 mayalso be provided in a dry form having sodium bicarbonate printed orpainted thereon in strips 518, or in other patterns. When the cleaningpad 514 is of the pre-moistened type, it may not be necessary to use thefluid reservoir 506. During use, the fluid from the pad 514 and/orreservoir 506 moistens the cleaning pad 514 and releases the sodiumbicarbonate onto the surface being cleaned, where it helps chemicallyneutralize offensive odors, and may serve as a mild abrasive to helppolish the surface.

In a variation of this embodiment, shown in FIG. 5C, the sodiumbicarbonate 519 is contained in a tray 520 on the cleaning head 504 in asolid or powdered form. The fluid hose 508 enters the tray 520 and fluidfrom the reservoir 506 saturates the sodium bicarbonate and releases itonto the surface being cleaned through holes 522 on the bottom of thecleaning head 504. In a further variation of this embodiment, the fluidhose 508 is instead attached to deposit fluid onto the floor or into thecleaning pad 514, and the sodium bicarbonate is deposited in a powderform 524. In still another variation of the invention (not shown), thesodium bicarbonate may be provided as a liquid mixture that is containedin the reservoir 506, and deposited into the cleaning pad 514 ordirectly on the floor when desired.

It is also envisioned that the sodium bicarbonate can be provided in asolid form and ground into a powder when odor removal is desired.Variations on this embodiment are shown in FIGS. 6 and 7A-7G. Thesedeposition systems may be used in conjunction with any type of vacuumcleaner, central vacuum system, extractor, or cleaning wand. A first ofthese embodiments is shown in FIG. 6. In this embodiment, the sodiumbicarbonate deposition system 600 comprises an electric motor 602 orair-turbine drive that rotates an abrasive drum 604. A solid sodiumbicarbonate block 606 is located adjacent the abrasive drum 604, andbiased against it by a spring 608. When the drum 604 rotates, it abradesthe block 606 and deposits powdered or fragmented sodium bicarbonate onthe surface being treated, onto a cleaning pad, into a fluid reservoirfor mixture with fluid therein, or into a dustcup or dustbag interior.This deposition system 600 can be controlled either by selectivelyoperating the motor 602, or by selectively contacting the sodiumbicarbonate block 606 against the abrasive drum 604. The degree ofsodium bicarbonate deposition can be controlled by altering the speed ofthe drum 604 or the pressure or speed at which the block 606 is fed intothe drum 604, or the surface area of the block 606 contacting the drum604. Of course, in other embodiments, the drum 604 may be replaced byother abrading devices, such as a rotating disk, a reciprocating file,and so on. In still other embodiments, the drum 604 or other abradingdevice may be turned manually by the vacuum operator, via a hand-crank,turning knob, or other suitable mechanism.

Referring now to FIGS. 7A-7G, another embodiment of a deposition system700 comprises a solid sodium bicarbonate bar or rod 702 that can beground manually by the vacuum operator. While the deposition system 700may be located anywhere where the sodium bicarbonate particles 708 canmingle with the dirt captured by the vacuum cleaner, in a preferredembodiment, it is attached to a dustcup lid 701, as shown in FIG. 7A, toenable the sodium bicarbonate particles 708 to be deposited directlyinto a dustcup interior. In this embodiment, the deposition system 700is located generally at the top of the dustcup lid 701, which in turn ismounted to the top of a dustcup 716 of a conventional cyclonic ordustcup vacuum cleaner. Here, the deposition system 700 is easilyaccessed by a user.

Referring to FIGS. 7B and 7C, a pocket or recessed area 703 is providedin a dustcup lid 701. The pocket 703 is constructed of a size andgeometry to at least partially accept and hold the sodium bicarbonatebar 702. The pocket 703 is in communication with the dustcup interior byone or more holes 707 to allow abraded particles 708 to easily drop intothe dustcup interior. A spring 710 is provided within the pocket 703,and opposite the abrasion surface 705, to bias the bar 702 against anabrasion surface 705, which is mounted on a movable plunger 704. Apocket cover 706 is also provided to retain the bar 702 within thepocket 703. The pocket cover 706 is preferably pivotally attached to thedustcup lid 701 as shown in FIG. 7C. (The pocket cover 706 is not shownin FIG. 7B, 7D, or 7F, to preserve the clarity of those Figures.)Alternatively, the cover 706 may be completely removable or omitted. Thepocket cover 706 may be secured to the dustcup lid 701 and pocket 703 bya latch, snap, friction fitting, or other attachment devices asgenerally known in the art.

The plunger 704 and abrasion surface 705 are provided on the dustcup lid701 and positioned such that the plunger 704 slides the abrasion surface705 relative to the sodium bicarbonate bar 702. This relative movementabrades the bar 702 and creates sodium bicarbonate particles 708, whichfall through a hole 707 into the dustcup. The plunger 704 and abrasionsurface 705 may be formed integrally as a single part, or mayalternatively be manufactured as two separate and assembled oroperatively associated pieces. The plunger 704 is also preferably biasedby a spring 711 in an up position requiring the operator to only pushthe plunger 704 to grind the bar 702. This arrangement allows the userto press and release the plunger 704 repeatedly until the desired amountof sodium bicarbonate particles 708 is generated.

Alternatively, the plunger 704 may instead be biased in a down positionor not biased at all. If the plunger 704 is not biased in eitherdirection, the user will have to both push and pull on the plunger 704to generate the particles 708. If the plunger 704 is only biased in adown position, then the user will only need to pull and release theplunger 704. Requiring a user to pull on the plunger 704 will likelyrequire a pull handle on the plunger 704. For simplicity, such a handleis not depicted.

Other variations of the plunger-style deposition system 700 may includea side moving plunger 704, an electrically powered plunger 704, or acombination of both. Examples of electrically powered plungers mayinclude coupling the plunger 704 to a solenoid, linear motor, or anelectric motor or air-turbine drive coupled to the plunger 704 via acam, crankshaft and piston combination, or other mechanical arrangementto create the linear motion. Such electric and mechanical devices aregenerally known in the art and are therefore not shown.

The abrasion surface 705 should be manufactured from a material hard andtough enough to successfully abrade the sodium bicarbonate bar 702 andnot break apart itself. Most hard plastics, such as structural ABSplastic, should be suitable. The abrasion surface teeth 712 should bespaced sufficiently apart to reduce the likelihood of sodium bicarbonatepowder and dust accumulating on the abrasion surface 705 and reducingthe abrasion surface's effectiveness. In addition, the abrasion surface705 may be provided with teeth 712 that cut on the pushing stroke, thereturn stroke, or both.

Other variations on the abrasion surface 705 provide openings 713 in theabrasion surface 705 between the teeth 712. These openings 713 allowfreshly abraded sodium bicarbonate particles 708 to pass from the sodiumbicarbonate bar 702 and through the abrasion surface 705 to reach thedustcup interior. Any powder accumulating between the teeth 712 would bepushed through these openings 713 at the abrasion surface's 705 nextpassing over the sodium bicarbonate bar 702. Thus, openings 713 in theabrasion surface 705 act to reduce the likelihood of sodium bicarbonatepowder sticking between the abrasion surface teeth 712 and reducing theabrasion surface's 705 effectiveness.

Another element of deposition system 700 of FIGS. 7B and 7C is a gasket709 that seals the dustcup lid 701 at the deposition system 700. Thegasket 709 comprises a resilient membrane that covers the plunger 704,with the plunger 704 being on the dustcup interior side of the gasketmembrane. The gasket 709 passes between the lid 701 and the pocket cover706 to allow access to the cover 706. The gasket 709 may be molded ormachined in to the desired shape prior to attachment to the lid 701, ormay be thermoformed to the proper shape after attachment. The gasket 709is preferably made of a resilient elastomeric compound such as,neoprene; isobutene-isoprene, commonly known as butyl; ethylenepropylene diene monomer, commonly known as EPDM; hydrogenated nitrilebutadiene rubber, commonly known as HNBR; or HYPALON® sold by DupontPerformance Elastomers of Wilmington, Del. Any suitable means may beused to attach the gasket 709 to either the dustcup lid 701 or thepocket cover 706. For example, the gasket may be attached by anadhesive, ultrasonic welding, heat sealing, laser welding, chemicalbonding, or, if the lid 701 or cover 706 are plastic, molded in placeduring an injection molding process. Such methods are generally known inthe art.

As shown in FIG. 7C, the gasket 709 seals the lid 701 by passing overthe plunger 704, and beneath the pocket cover 706. Alternatively, thegasket 709 may be provided only around the plunger 704, only around thepocket cover 706, or omitted entirely. When used, the gasket 709 helpsprevent dust or debris from spilling from the dustcup during vacuum idletime, and also ensures that no sodium bicarbonate powder will leak outwhile the cover 706 is closed. The sealing gasket 709 also reduces airleakage through the deposition system 700 to thereby decrease suctionloss at the inlet nozzle.

The embodiment of FIGS. 7B and 7C is expected to be particularly usefulwhere the deposition system 700 is positioned above the location whereit is desired to mix the sodium bicarbonate with the dirt, as gravitycan easily convey the particles 708 to the desired location. However, inthis arrangement, sodium bicarbonate particles 708 may accumulate in thebottom of the pocket 703 and spill out when the operator opens the cover706 to insert a new bar 702. Sodium bicarbonate particles 708 may alsoaccumulate on the abrasion surface 705 and reduce its effectiveness inabrading the bar 702. To address these potential problems, othervariations of the invention provide vacuum assistance in delivering thesodium bicarbonate particles 708 to the dustcup interior (or other finaldestination). These embodiments do not have a gasket, or purposefullyleave an opening in or around the gasket 709, pocket cover 706, orplunger 704 to allow the vacuum to generate an incoming flow of air toconvey the particles 708 into the vacuum. It will be appreciated thatthe use of a controlled incoming airstream may also allow the depositionsystem 700 to be used where gravity cannot be relied upon to convey thesodium bicarbonate particles 708 to the dirt.

A first example of the foregoing variations of the invention is shown inFIGS. 7C-7D. In this embodiment, the deposition system 700 is generallythe same as the embodiment of FIGS. 7B-7C, and has a sealing gasket 709.However, this embodiment includes an opening 714 in the cover 706 thatallows airflow to enter the pocket 703 and clean out any lingeringsodium bicarbonate particles 708. The use of such an opening 714potentially gives manufacturers and designers more control over whereand how the airstream 715 enters and moves through the pocket 703. Inthe shown embodiment, the opening 714 passes through the cover 706 justabove the abrasion surface 705 to maximize the airflow at this point.Another embodiment provides the cover 706 with an internal duct taking atortuous path to the pocket 703 to help reduce the likelihood of anysubstantial amount of dust or sodium bicarbonate particles 708 escapingfrom the dustcup during vacuum idle time.

Referring to FIGS. 7F-7G, another embodiment of the invention comprisesan opening 714 formed in the plunger 704, which directs the airstream715 through the abrasion surface 705. This embodiment helps deliver theparticles 708, and helps prevent sodium bicarbonate particles 708 fromaccumulating between the teeth 712 on the abrasion surface 705. Stillother variations on a deposition system 700 having a controlled airentry will be appreciated by those of ordinary skill in the art in viewof the present discussion.

The manual deposition system 700 of FIGS. 7A-7G may be placed on adustcup sidewall, above or adjacent to a dustbag inlet, or on any vacuumcleaner duct or conduit. As noted before, the use of a controlled airentry path may also allow the system 700 to be used in locations wheregravity is not available to draw the particles 708 into the vacuum. Thisair assist can also be increased by locating the hole 707 in the pocket703 adjacent a relatively low pressure part of the vacuum path, such asadjacent a hose, or at a venturi located in a hose. The system may alsobe placed on a floor nozzle and be foot actuated, where the particles708 can be deposited directly on the carpet or surface being vacuumed ordirectly into the vacuum airstream. The amount of sodium bicarbonatedeposited can be controlled by altering the stiffness of the biasingspring 710, the number, pattern, and orientation of the teeth 712 on theabrasion surface 705 and by other modifications, as will be appreciatedby those of ordinary skill in the art.

The present invention also contemplates using heat to provide controlleddeposition of sodium bicarbonate into the vacuum cleaner. In a furtherembodiment of a deposition system 810, shown in FIG. 8, the sodiumbicarbonate is provided as a powder that is held together in atemperature-sensitive matrix to form a solid block 812. The block 812 islocated in a cage 814 or other perforated chamber, and selectivelyheated to cause the matrix to soften or evaporate. The cage 814 isprovided with vents 818 that are sufficient to allow airflow to passthrough the cage 814 and to the sodium bicarbonate block 812 and may bemade of a thermally conductive material to heat the block 812 byconduction. As the matrix erodes, the sodium bicarbonate is releasedthrough the cage vents 818 and onto the surface to be cleaned or into afluid reservoir (if used in an extractor). A separate heater may beprovided to heat the sodium bicarbonate block 812, or heat may beprovided from a vacuum motor 816 or other heat source already present inthe device.

An additional variation on this embodiment provides airflow vanes (notshown) on the cage vents 818, and means to rotate the cage 814 duringvacuum operation. As the cage 814 rotates, the vanes draw air into thecage 814 and to the sodium bicarbonate block 812. The cage 814 may berotated by the vacuum motor 816, or by a vacuum airflow drivenair-turbine drive or other motor, or the vanes may be moved by anincoming airflow (such as the fan motor exhaust). In addition, thesodium bicarbonate block 812 may be secured to the rotating cage 814, ormay be stationary relative to the rotating cage 814. The vanes may alsoact as additional heat sinks to help heat the block 812 by conduction.

In another embodiment, shown in FIGS. 9A-9C, the present inventionprovides a chemically-impregnated loose sheet 900 that can be insertedinto a vacuum cleaner dirt bag or other vacuum cleaner dirt container.The sheet 900 comprises a fabric or other material that is impregnated,coated, or otherwise provided with odor-reducing materials, perfumes orother compositions that are useful for killing bacteria, reducing odors,creating pleasant odors, or otherwise making the operation of the vacuumcleaner more pleasant or sanitary. In a preferred embodiment, the sheet900 is impregnated with sodium bicarbonate, but other materials may beused. The sheet 900 preferably comprises a woven or non-woven fabricmaterial, which may be air permeable or not. The fabric may alsocomprise a uniform material, or a composite of multiple types and/orlayers of material. In a preferred embodiment, the fabric comprises aweb of non-woven polyester fibers that are arranged in a random,non-directional manner, and needles to increase the size of the voidareas between the fibers to provide additional loft. The fibers may havea coarse or fine denier, and may have a combination of deniers. Asuitable material is TYVEK™, which is distributed by E.I. du pont deNemours and Co. of Richmond, Va. Other suitable materials includenon-woven polyester fabrics such as PN232 and PC858 manufactured by thePrecision Custom Coatings Company of Totowa, N.J. Of course, any othersuitable material, such as a cotton weave, a non-woven polymer, orothers, may be used.

Referring to FIGS. 9A and 9B, a sheet 900 of this embodiment of theinvention may be inserted into any conventional vacuum cleaner dirtcontainer to help reduce odors and provide other benefits to thecleaning device operation. To this end, the sheet 900 may be provided ina package 902 with multiple sheets 900 therein, and directions forinserting the sheets 900 into the cleaning device for which its use isintended. Such a package 902 may be adapted to be held in the cleaningdevice itself, such as by being located in a pocket or slot in a vacuumcleaner housing. The cleaning device itself may also be modified to holdsheets 900 when they are not in use. The sheet 900 may alternatively beprovided as a perforated roll 903 of material that may be torn to formindividual sheets 900 or sachets filled with active material, or in anyother suitable form.

When used with conventional dust bag filters, the sheet 900 may besimply inserted into the bag inlet before it is attached to the vacuumcleaner. When used with dirt cup filters, such as the cyclone separator904 shown in FIG. 9C, the sheet 900 may be attached to the dirt cup 906by one or more clips 908, or other mechanical or adhesive bonds, toprevent it from wrapping around or otherwise obstructing the cycloneoutlet or filter 910. In this embodiment, the sheet 900 may be heldtightly in place, or allowed to move into and with the airflow (asshown) to interact with the dirt contained in the dirt cup 906. Theshown location of the sheet 900 at the bottom of the cup 906 ispreferable to allow the sheet 900 to react with the dirt when the vacuumcleaner is not in use, but this is not required.

Referring now to FIGS. 10A-10H, in a preferred embodiment of theinvention, a deodorizing sheet 1000 is provided pre-installed andpermanently or removably attached to a bag filter 1012. Preferably, thedeodorizing sheet 1000 comprises at least one sheet layer having sodiumbicarbonate (and/or other deodorizing compounds) operatively associatedwith it. Such operative association may be by capturing the sodiumbicarbonate within the fibers of the sheet or between multiple sheetlayers, adhering the sodium bicarbonate to the sheet material, or by anyother technique that generally applies the sodium bicarbonate to thesheet. While firm attachment of the sodium bicarbonate to the sheet maybe provided, it may also be desirable to allow the sodium bicarbonate torelease from the sheet, at least to some degree, during installationand/or operation. Such release is referred to as “dusting.” Furthermore,while particular embodiments of sheet material are described herein, theterm “sheet” is understood herein to describe any generally flatmaterial, which may be flexible or not.

A typical bag filter comprises one or more air pervious flexible sheetsof material that are assembled together to form a generallyair-permeable enclosure. The exemplary bag filters 1012 shown hereincomprise sidewalls 1013, one or more optional end walls 1023 (onlydepicted in the embodiment of FIGS. 10G and 10H), an inner surface 1014,an outer surface 1015, and rolled end crimps 1022 to sealingly close oneor both ends of the bag 1012. The sidewalls 1013 are typically formedwith expandable pleats to allow the bag 1012 to expand to inflate to alarge volume capacity during use, yet efficiently fold compactly forpackaging and shipping to the consumer. The sidewalls 1013 and/or endwalls 1023 comprise an air-permeable filtering material that allows airto pass through them, but captures dirt and debris within the enclosureformed by the walls. Bag filters and the materials from which they canbe made are well known in the art, and as such a detailed discussion ofthem is not necessary here. It will be understood that the presentinvention may be used with any kind bag filter, including those havingpaper walls, non-woven walls, and so on.

A flange 1020 is adhered to an opening in the bag 1012 to form an inlet1016. The flange 1020 adds stability to the inlet 1016 and furtherassists in sealing the bag 1012 to the vacuum cleaner. The flange 1020is preferably made from cardboard, paperboard, or plastic. The flange1020 and inlet 1016 may be placed on a sidewall 1013 (FIGS. 10A-10F) oran end wall 1023 (FIGS. 10G and 10H). Furthermore, an annular rubberseal (not shown) may be provided at the inlet 1016 to assist withsealing the bag to the vacuum mounting tube. Such seals are generallyknown in the art, and may comprise a soft, resilient material thatelastically surrounds a mounting tube onto which the inlet is placed,such the mounting tube 115 shown in FIG. 1. Other flange features mayinclude lock-out tabs that engage with a mechanism that prevents closureand/or of the vacuum cleaner when the filter bag is not in place,handles to facilitate bag installation and/or removal, and inlet closuredoors that slide or pivot in place to cover the inlet 1016 when the bag1012 is removed from the vacuum cleaner.

The sodium bicarbonate sheet 1000 may simply be placed inside the bagfilter 1012, but more preferably is adhesively bonded or sewn to theinner surface 1014 of the bag filter 1012. The location and airpermeability of the sheet 1000 can be modified to obtain severalexpected beneficial results. In a preferred embodiment, the sheet 1000is adhered to the inner surface 1014 with an air-impermeable adhesivethat covers about 5%, to about 20% of the sheet area, and mostpreferably about 6% of the sheet area. In this embodiment, the sheet1000 is preferably substantially air permeable, to generally reduce thebag's overall resistance to air flow, but it is believed that the use ofsubstantial area of air-impermeable adhesive will block some airflow todeflect the air through the plane of the sheet to agitate the sodiumbicarbonate and release it into the bag 1012. Alternatively, the sheet1000 may be mostly or completely air-impervious, or provided with an airimpermeable backing, which would increase the bag's overall airflowresistance, but is expected to cause the incoming air to strike andtravel along the sheet to better distribute the sodium bicarbonate intothe bag's interior.

As shown in FIGS. 10A-10D, the sheet 1000 is preferably attachedimmediately opposite the air inlet 1016 into the bag filter 1012, sothat the incoming air flow 1018 strikes the sheet 1000 and mixes withthe sodium bicarbonate or other chemicals in the sheet 1000. In thisway, the sheet 1000 acts as a sacrificial element that is replaced witheach replacement of the bag filter 1012. Also in this embodiment, thesheet 1000 may be formed of or layered with an anti-penetration barrier(not shown) to help prevent objects carried by the incoming airstreamfrom penetrating the bag filter 1012. Examples of such materials areshown in U.S. Pat. No. 5,690,711, which is incorporated herein byreference. In a preferred embodiment, the anti-penetration layercomprises a relatively tough material, such at TYVEK™ (a web ofhigh-density polyethylene fibers that are arranged in a random,non-directional manner), to help protect the filter bag 1012 from beingpunctured by hard objects that may enter the filter bag 1012. The sheet1000 may also comprise a foam material or layer, or other loftymaterial, which may prevent bag penetration by cushioning incomingobjects before they strike the bag inner surface 1014. Theanti-penetration barrier, if one is used, is preferably positionedimmediately adjacent the inner wall of the bag filter.

In a preferred embodiment, such as the ones in FIGS. 10A-10H, a singlesheet 1000 formed of one or more overlapping sheet layers and sodiumbicarbonate particles is positioned in the bag filter 1012. In anotherpreferred embodiment, one or more sheets 1000 may be used, but theycover less than about 30% of the bag filter's working surface area (thatis, the area of the bag filter walls through which air generally passesin use, which excludes the surface covered by the flange and rolledpleated ends, but includes the area covered by the sheet 1000 itself),and more preferably less than about 25% of the working surface area. Ineven more preferred embodiments, the sheet 1000 or sheets cover about4-15% of the bag filter's working surface area. The foregoingconstructions are believed to improve upon the prior art, which has usednumerous attached sheets that cover the majority of the bag's workingsurface or has treated the filter walls themselves with deodorants. Incontrast, the foregoing embodiments do not require the filter wallsthemselves to be treated with deodorizing compound, do not requiremultiple separate sheets (if a single sheet is used) to be attached,both of which increase the overall expense of the device. Furthermore,it has been discovered that using deodorizing sheets that cover less ofthe filter bag, rather than more (as appears to be the trend in theprior art), actually provides suitable deodorizing both during use andduring latent periods. As such, the foregoing embodiments of the presentinvention provide a single sheet (or multiple small sheets) over arelatively small area, which eases manufacturing requirements, reducesraw material costs (including, for example, costs of the sheetsubstrate, sodium bicarbonate, and adhesive or other bonding devices),and still provides a noticeable odor reduction in the vacuum cleaner.Despite the expected advantages of the foregoing embodiments, otherembodiments of the invention provide separate and distinct advantagesover the prior art, and such embodiments may use multiple separate oroverlapping deodorizing sheets in a single bag filter 1012, and they mayexceed the coverage percentages listed above.

Referring specifically to FIGS. 10C and 10D, another preferredembodiment may also include an air restricting layer 1001 on the innersurface 1014 or, more preferably, the outer surface 1015 of the bag 1012overlying the sheet 1000. In the preferred embodiment, the restrictinglayer 1001 is a blocking emulsion printed in a dotted pattern on theouter surface 1015, but may take other forms such as adhered paper,cardboard, metal foil or plastic laminate, or a simple application ofadhesive, any of which may be perforated to allow some air-permeability.The air restricting emulsion 1001 of the preferred embodiment reducesairflow through sheet 1000 by approximately 30% to 90%, and morepreferably about 60% to about 70%, and most preferably about 66%. Butmore or less restriction may be desirable, and it may even be desirableto have up to 100% restriction. The air restricting layer 1001 may beremovable to allow the user to control, to some degree, the airflowthrough the deodorant sheet 1000, but it is more preferred for the airrestricting layer 1001 to be permanently attached.

In operation, the incoming stream of dust-laden air 1018 enters thedustbag 1012, and strikes the sheet 1000. The restricting layer 1001redirects some or all of the air to the bottom of the bag 1012. Theturbulent airflow created by this drastic airflow redirection dislodgesthe active ingredients of the deodorizing mix from the sheet 1000, andallows the sodium bicarbonate and other deodorizing agents to morereadily mix with the air and dust. Such dislodged particles remain incontact with the dust while the vacuum sits idle, increasing theeffectiveness of the deodorizers. This is useful because a vacuum's idletime is typically much greater than its operational time.

Referring to FIGS. 10E-10H, another embodiment of the present inventioncomprises a sheet 1000 at or near the bottom of the bag 1012—that is, atthe bottom of the bag 1012 as it is oriented when mounted in a vacuumcleaner. This places the sodium bicarbonate and other active ingredientsin the sheet 1000 in close proximity to the dust and debris in the bag1012, and promotes odor neutralization during idle time.

In the embodiment of FIGS. 10E and 10F, the bag 1012 comprises atwo-paneled construction formed by two sheets with the flange 1020located on the side of the bag 1012. The embodiment of FIGS. 10G and 10His similar, but uses a three paneled construction with the flange 1020located at the end of the two side sheets.

A preferred embodiment for producing an impregnated sheet for use withthe present invention is depicted in FIGS. 11A and 11B. The sheet 1134produced by this process comprises first and second sheets 1120, 1130and a dry deodorizing mixture 1126. The deodorizing mixture 1126comprises a blend of deodorant, adhesive, and other useful compounds, ifdesired. In a preferred embodiment, the deodorizing mixture 1126 is adeodorizer comprising of 91.5 wt. % (weight percentage) sodiumbicarbonate, such as ARM & HAMMER™ baking soda (with grades 2 and 5being particularly useful), 5.0 wt. % 11P23 hot melt adhesivemanufactured by EMS Griltech of Sumter, S.C. (“GRILTEX™ hotmelt”—aheat-resistant, polymer-containing, solvent-free binder), and 3.5% wt. %MOLSIV™ Adsorbents Smell Rite® Zeolite manufactured by UOP L.L.C. of DesPlaines, Ill. (a synthetic sodium aluminum silicate with a zeolitestructure that has been treated to be adsorptive of odoriferouscompounds, and has organophilic micropores that attract and trap odormolecules). The deodorizing mixture 1126 may be mixed in a pre-cleanedribbon mixer or other suitable high shear powder mixer for sufficienttime to fully blend the chemicals.

Other useful compounds that may be used with the present inventioninclude, but are not limited to, activated carbons, activated charcoal,diatomaceous earths, cyclodextrin, quaternary ammonium salts, silanequaternary ammonium salts, clays, fragrance oils, and the like. Suitablemixtures include, for example, about 50-100 wt. % (weight percentage) ofsodium bicarbonate, about 0-10 wt. % of zeolites, about 0-20 wt. % ofactivated carbon, about 0-5 wt. % of quaternary ammonium salts, about0-5 wt. % of silane quaternary ammonium salts and about 0-2 wt. % offragrance oils. In a preferred embodiment, the adhesive may be providedas about 2-6 wt. % of the deodorant composition, but may alternativelybe provided as about 5-15 wt. %, and more preferably about 5-10 wt. % tobetter adhere the deodorizing particles to the sheets and adhere thesheets to one another.

The first non-woven sheet 1120 preferably comprises a non-wovenpolyester sheet with a thickness of 1.88 mm. Such a sheet is sold asstyle PN 232 by the Precision Custom Coatings Company of Totowa, N.J.Other suitable sheet materials may have a thickness of about 0.05 to6.00 mm and a basis weight of about 25 to 200 gsm (grams per squaremeter). More preferably, the first sheet 1120 is about 0.50 to 4.00 mmthick, or even more preferably about 1.00 to 3.00 mm thick. Suitablealternative materials include, for example, natural fibers, othersynthetic fibers, or open cell foams. The sheet is provided as a roll1121 (as shown), as separate sheets, or manufactured from raw materialson the manufacturing line itself. When provided in a roll 1121, thesheet 1120 may be passed through a sheet spreader 1122, which pulls thesheet 1120 laterally, to make the sheet taut. The sheet 1120 then passesunder a sifter 1124, or other type of deposition device, such as avibratory feeder, which deposits the sodium bicarbonate deodorizingmixture 1126 onto the sheet 1120. It has been found that a portion ofthe mixture 1126 sinks down into the thickness of the sheet 1120, butmuch of it remains at or near the sheet's surface.

The sheet 1120, with the deodorizing mixture 1126 sifted onto it, thenpasses through a curing oven 1128. Heating lamps, hot air, or any othersuitable heat source may be used in the oven 1128. The oven 1128 heatsthe surface of the sheet 1120 to melt the hot melt adhesive in themixture 1126 and thereby bind the sacrificial deodorizing elements ofthe deodorizing mixture 1126 to the sheet 1120. A suitable temperaturefor the process is a sheet surface temperature of about 100° F.-300° F.,and more preferably about 270° F. or 280° F.-300° F. The foregoingtemperatures have been found to be suitable to bind the deodorizingcompounds in place without damaging them or the sheet 1120, and withoutunduly coating the deodorizing compounds with adhesive.

It will be understood that the temperature and length of time in theoven can be adjusted to obtain the most favorable coating of the hotmelt adhesive on the deodorant components and the sheet 1120. Too muchheat may result in damage to the sheet 1120 or deodorants, or may causeexcessive coating of the deodorant by the adhesive. Too little heat mayresult in insufficient binding of the deodorant. Preferably, the sheet1120 is exposed to the heat just long enough to obtain a surfacetemperature of about 270° F. or 280° F. to 300° F., but this targettemperature may vary depending on the type of sheet material or amountor composition of the deodorizing mixture 1126. This target temperaturecan be varied by any suitable means, such as varying the line speed,oven length, oven temperature, and so on, as will be appreciated bythose of ordinary skill in the art.

After the first sheet 1120 emerges from the oven 1128, a second sheet1130 is laid on the first sheet 1120 to overlie the deodorizing mixture1126. The second sheet 1130 is provided to help capture the deodorizingmixture 1126 in place and reduce the dustiness of the finished product1134 but is air permeable to allow airflow to the deodorizing mixture1126. In the preferred embodiment, the second sheet 1130 comprises a PES(polyethersulfone) and rayon scrim with a thickness of about 0.203 mm.The Precision Custom Coatings Company of Totowa, N.J., sells such asheet as style PC 858. This second sheet 1130 is unwound from a roll1135 and pressed onto the first sheet 1120 and deodorizing mixture 1126after it emerges from the oven 1128, and while it is still warm. Rollers1132 compress the two sheets together at a pressure of about 50-200pounds per square inch of pressure, and more preferably about 80 poundsper square inch. By applying the second sheet 1130 immediatelydownstream of the oven 1128, it can be held in place by the still-warmhot melt adhesive, an no additional adhesive is required. Of course, aseparate adhesive may be used to supplement the hot melt adhesive, or ifit is desired to apply the second sheet 1130 at a location where the hotmelt adhesive in the deodorizing mixture 1126 is not longer warm.

As the adhesive cools, it adheres the two sheets 1120, 1130 and thedeodorizing mixture 1126 together. The finished product 1134 is about0.50-5.00 mm thick, and more preferably about 2 mm thick (with potentialfor significant variation caused by the handling process and due tovariations in the sheets' starting thickness and processing), with 3layers: the first sheet 1120, the deodorizing mixture 1126, and thesecond sheet 1130. FIG. 11B depicts these 3 layers. It will beappreciated that, while FIG. 11B shows the layers as being discrete,some intermingling may occur in practice, and up to 100% diffusion(i.e., uniform diffusion) of the deodorizing mixture 1126 into the firstand/or second sheet 1120, 1130 may be accomplished and used with theinvention, if desired. To obtain such high penetration, however, othermanufacturing methods may be necessary. Examples of other suitablemethods for impregnating a material to form sodium bicarbonate sheet aredisclosed in U.S. Pat. Nos. 6,099,101, and 6,302,946, which areincorporated herein by reference.

The process ends with the final product 1134 being rolled onto a finalroll 1135. This product 1134 may now be cut into various shapes andsizes and utilized as described herein, preferably, but not necessarily,with the second sheet 1130 facing inwards into the bag filter. Thefinished product 1134 is preferably cut with an ultrasonic, thermal, orother self-sealing process. A self-sealing process binds the layers ofthe sheet together at the cut, and thus ensures minimal loss of thedeodorizing mix 1126 after cutting. If a self-sealing method is notemployed, then the amount of deodorizing mix 1126 may be increased,preferably by about 5% to 10% to account for the losses that may occurin the manufacturing process, and/or the amount of adhesive mayoptionally be increased to about 5-15 wt. %, and more preferably toabout 5-10 wt. % to ensure sealing of the sheets and adherence of thedeodorizing composition.

The size of the finished sodium bicarbonate impregnated sheet will vary,depending on the amount of dirt that is expected to accumulate in theparticular application in which the sheet is used. Larger sheetsgenerally would be used when greater amounts of dirt are expected toaccumulate. Deodorizing sheets made from the previously describedprocess have been found to be effective in reducing the odor releasedfrom a vacuum cleaner when cut to sizes ranging from 16 in² to 40 in²and when used to replace a standard filter used in a bagless vacuumdustcup. Smaller sheets, as small as 2 in² or even smaller, may beeffective in small handheld vacuums, and much larger sheets may be usedin large-capacity shop vacuums and central vacuums. It is believed thatin applications in which the sheet is used within a dirt container (asopposed to being outside the actual dirt container, as in the case ofsheets used, for example, with post-motor filters) there is a directlyproportional relationship between the size of the dirt container and thesize of the sheet necessary to provide effective odor prevention.

A preferred embodiment, such as one that is preferred to be used withthe embodiments of FIGS. 10A-10H, has approximately 10 ounces ofdeodorizing mixture 1126 per square yard of sheet, or 10 oz/yd². Theamount of deodorizing mixture 1126 per square yard of sheet isdetermined by the following equation:

${{Load}\left( {{oz}/{yd}^{2}} \right)} = \frac{{Spread}\mspace{14mu} {{Rate}\left( {{oz}/\min} \right)}}{{Fabric}\mspace{14mu} {{Speed}\left( {{yd}/\min} \right)}*{Fabric}\mspace{20mu} {{Width}({yd})}}$

“Load” represents the amount of deodorizing mixture per square yard ofsheet with 10 oz/yd² being the preferred amount. “Spread Rate,”expressed in oz/min, represents the rate the deodorizing mixture 1126 isspread onto the non-woven sheet 1120. “Sheet Speed” is the linear speedthe sheet 1120 passes under the sifter 1124, and is expressed in yd/min.Finally, “Sheet Width” is the lateral width of the sheet as expressed inyards. Given the equation above, one skilled in the art can determinethe parameters required to deposit 10 oz of mixture 1126 onto 1 squareyard of sheet. One embodiment provides a spread rate of 40 oz/min, whichwould require a sheet speed of 4 yds/min for a 1 yd wide sheet.

Referring now to FIGS. 12A and 12B, another process to manufacture achemically impregnated sheet is described. This embodiment starts with aroll 1241 of non-woven sheet 1240. The sheet 1240 first passes under asifter 1224, which deposits an even layer of deodorizing mixture 1226 onthe sheet 1240. In this embodiment, the deodorizing mixture 1226includes sodium bicarbonate, a water soluble adhesive, and any otheruseful deodorants or fragrances, if desired. The sheet 1240 anddeodorizing mixture 1226, then pass over a rotating cam 1244. The cam1244 continuously rotates through 360° about an axis that is parallel tothe plane of the sheet and perpendicular to the path of the sheet. Thecam 1244 has one or more eccentric lobes that strike the sheet 1240 andimpart vibrations thereto to work the mixture 1226 into the sheet 1240fibers. The cam 1244 of FIG. 12B has two lobes, and is shown in twodifferent positions representing the two extremes through which the cam1244 rotates. When the cam 1244 is in a first position, it is in lightcontact or out of contact with the sheet 1244. When the cam 1244 rotatesto a second position, shown in phantom lines, it presses against anddisplaces the sheet 1240. Thus, as the cam 1244 rotates, it pushes thesheet up and down and generally creates a first order standing wave withstationary nodes located at the sheet rolls 1241, 1251 at each end ofthe process. Other embodiments may include more cams, cams having avaried number of lobes, cams with lobes of varying dimension, camsplaced on top of the sheet, and cams with constant or variablerotational speeds. Pinch rollers may also be provided to isolate thevertical displacement caused by the cam 1244.

After the deodorizing mixture 1226 is applied to the sheet 1240 andagitated into the sheet 1240 by the cam 1244, the sheet 1240 and mixture1226 pass under a hot water vapor mist 1246 or a warm water spray. Thewater or water vapor mist 1246 emulsifies the adhesive so that theadhesive bonds the sodium bicarbonate to the fibers of the non-wovensheet 1240. After being impregnated with sodium bicarbonate in thismanner, the sheet 1240 passes into an oven (as shown above) or under afan 1248, which may also have an air heating element, to evaporateexcess moisture and dry the impregnated material. As the adhesive coolsand dries, it bonds the deodorizing elements of the mixture 1226 to thesheet 1240 and creates an impregnated sheet designated as 1250. Sheet1250 is collected onto a final roll 1251, and may now be cut intovarious shapes and sizes and utilized as described herein. Across-section of the sheet 1250 is illustrated in FIG. 8D with the mix1226 dispersed within the sheet 1240.

It should be noted that in the foregoing embodiment, the hot water vaporstep 1246, may be omitted if the operation of the cam 1244 is suitableto obtain the desired penetration of the mixture 1246 in the sheet 1240.

It will be understood that the foregoing embodiments are exemplary only,and variations of these embodiments and other embodiments will beapparent to those of ordinary skill in the art in light of the teachingsprovided herein. In addition, it may be possible to mix the steps of thetwo processes described herein. As an example, the rotating cam 1244 ofFIGS. 12A and 12B may also be used with the embodiments of FIGS. 11A and11B. It will be understood that the foregoing depictions ofmanufacturing systems and procedures are not intended to be exclusive ofother features and steps. For example, either of the foregoingembodiments may include additional features such as loose powderrecovery systems, vacuum assisted particle penetration devices that drawa vacuum on one side of the sheet to pull the particles deeper into thesheet, accumulators, and so on.

Referring now to FIGS. 13A-13C, another embodiment of a chemicallyimpregnated sheet is depicted as disk 1300. Disk 1300 is circular andformed from open cell foam, non-woven high loft fabric 1301, or othermaterials, and can be used in the same way as other sodiumbicarbonate-impregnated sheets described herein.

To manufacture this embodiment, the disk 1300 is spun horizontally at ahigh rotational speed, while a sodium bicarbonate slurry 1302 is addedto the disk center 1304, which is located at the vertical axis ofrotation. The resulting centrifugal force slings the slurry away fromthe center 1304, as shown by the arrows, and distributes the slurry 1302throughout the disk 1300. After the slurry 1302 is sufficientlydistributed, the disk 1300 may be further spun to sling out excess waterand assist with drying. Additional or alternative methods of drying thedisk 1300 may include subjecting the disk 1300 to a heat source,forced-air convection, or a combination thereof.

Preferably, the sodium bicarbonate is dyed yellow, and the disk fabric1301 is white, to provide a distinctive and unique appearance.

Referring to FIG. 13C, a variation of the embodiment of FIG. 13A, alsoincludes activated carbon 1311. The activated carbon 1311 preferably isprovided in a slurry 1312 and applied around the perimeter of the diskto create a distinctive and unique appearance. Alternatively, theactivated carbon 1311 may be added to the sodium bicarbonate slurry1302, or may be diffused, as described above, in a separate sheet diskand adhered to disk 1300.

Slurries 1302, 1312 may also be provided with a hot melt adhesive,similar to the hot melt adhesive contained in mix 1126. If a hot meltadhesive is provided, then it will also be necessary to subject disks1300, 1310 to a heat source, such as a forced-air convection oven, toactivate the adhesive. This heating process would be similar to the ovenprocess 1148 shown and described in FIG. 8C and accompanying text.Alternatively, the slurry may be heated before being applied.

Other methods will be readily apparent to those of ordinary skill in theart in view of the present disclosure, and such other methods areincluded within the scope of the invention. Non-limiting examples ofsuch variations include forming the sodium bicarbonate sheet as alayered non-woven material having powdered sodium bicarbonatedistributed between or within the layers, or coating a sheet with sodiumbicarbonate on its exterior surfaces.

Example 1

Tests were conducted using Eureka Model 402 vacuum cleaners. The EurekaModel 402 vacuum cleaners were bagless and contained a cone shapedfilter within the dust cup. A control filter was compared to a treatedfilter. The control filter was a standard untreated filter. The treatedfilter contained the deodorizing device of the present invention.

The deodorizing device included the deodorizing composition disposedbetween two nonwoven gas porous materials. The deodorizing compositioncontained about 91.5% sodium bicarbonate, 3.5% zeolite and 5% adhesive(GRILTEX™) and was coated on a 6.25 in.×6.25 in. size filter at acoating level of 8.7 oz/yd², (0.19 g/in²). The first nonwoven materialwas a moldable polyester having a fabric weight of 3.2 oz/yd² (108.5g/m²); tensile strength in the machine direction of 25 lbs; tensilestrength in the cross-machine direction of about 75 lbs; and thicknessof 74 mils (1.88 mm). The first nonwoven material served as the bottomlayer of the deodorizing device and was a heavier sponge-like nonwovenmaterial than the top layer. A suitable example of the first nonwovenmaterial was obtained under the trade designation PN232 available fromPrecision Custom Coatings LLC, Totowa, N.J.

The second nonwoven material used herein was a hydrophilic PES/rayonhaving a fabric weight of 0.75 oz/yd² (25.4 g/m²); tensile strength inthe machine direction of 10.8 lbs; tensile strength in the cross-machinedirection of 0.5 lbs; and thickness of 8 mils (0.203 mm). The secondnonwoven material served as the top layer of the deodorizing device. Thesecond nonwoven material was a “scrim” that minimized dustiness of theproduct and allowed for good air flow. A suitable example of the secondnonwoven material was obtained under the trade designation PC757,available from Precision Custom Coatings LLC, Totowa, N.J.

Each of the filtered dust cups was filled with soil that was enhanced toemit a noticeable household odor. The soil consisted of 50 grams of dampvacuum cleaner dust, 2.5 grams of cat urine (provided by Martin CreekKennels, of Williford, Ariz.), and 1.25 grams of Limburger cheese. Thecat urine provided a strong, characteristic pet odor and the Limburgercheese imitated human body odor and strong kitchen odors.

The Eureka Model 402 machines were equally loaded with soils and allowedto sit for 4 hours, and then placed inside cleaned new 30 gallon plasticgarbage cans. The cans were used to contain the air emitted from theexhaust of the vacuum. The plastic lids on the garbage cans had sniffingports cut into them through which panelists could sample the airtherein.

After the 4 hour gestation time, the lids were sealed and the vacuumswere activated for 5 seconds. The air ejected in this 5 second periodrepresents the most odorous air, usually encountered at machine startup.It was captured in the cans for panelists to sample.

Twenty panelists rated the two cans on a 0 to 6 scale for malodor. Arating of 0 represented the least odor, a rating of 6 represented themost odor. The following table shows the result from two separatetrials:

TABLE 1 Trial Control Treated #1 3.6 1.4 #2 3.8 1.1

In the test, the difference between the treated and control wasstatistically different at the 99% confidence level.

Example 2

Odor levels were measured in a sensory panel comparing a control sampleto two treated samples. The odor studied in this test was 100 grams ofdamp vacuum cleaner dust. The tests were conducted by disposing theodors inside a 2 quart enclosed space.

The control sample had only the odor in the container. The two treatedsamples had the odors in the container and the deodorizing devices ofthe present invention where 7.4 grams of the deodorizing compositionwere loaded between two 6.25 in. square pieces of nonwoven material. Thefirst “treated” sample contained 88% sodium bicarbonate, 7% Smellrite@,and 5% GRILTEX™ hotmelt on the nonwoven material. The second “treated”sample contained 91.5% sodium bicarbonate, 3.5% zeolite and 5% adhesiveon the nonwoven material.

Eighteen panelists smelled the odor inside the 2-quart enclosed spaceand rated the smells on a 0 to 6 scale for malodor. A rating of 0represented the least odor, a rating of 6 represented the most odor. Thefollowing table shows the result from the present test:

TABLE 2 Sample Odor Level Control 4.2 Treated Sample #1 2.8 TreatedSample #2 2.4

There was no statistically significant difference between the twosamples and both of the treated samples had a statistically significantlower odor source than the control.

It should be understood that the foregoing embodiments are exemplaryonly, and other embodiments will be apparent to those of ordinary skillin the art in light of the teachings provided herein. Furthermore, whilethe foregoing description illustrates the use of various embodiments ofsodium bicarbonate chemical neutralizers in use with various differenttypes of cleaning device, it will be understood that the embodimentsdescribed with respect to each device may also be used with the othertypes of the device. For example, the sleeve 122 described with respectto the bagless vacuum in FIG. 1 could be used in conjunction with thebagless vacuum of FIG. 2A, or the extractor of FIG. 4A. Other variationswill be apparent to those of ordinary skill in the art in view of thepresent disclosure and with practice of the invention.

1. A vacuum cleaner filter assembly comprising: a filter frame definedby one or more frame side walls; a filter mounted in the filter frameand extending between the one or more frame sidewalls, the filter havinga filter surface through which air can pass during use; a chamber havinga first chamber side wall adjacent and connected to a first portion ofthe one or more frame side walls and a second chamber side wall adjacentand connected to a second portion of the one or more frame side wallssuch that the entire chamber is positioned generally adjacent to a firstportion of the filter surface, the chamber having at least onefilter-facing portion facing the first portion of the filter surface,and defining a passage from the at least one filter-facing portion to aportion of the chamber not facing the filter; at least one deodorantcontained in the chamber; and wherein the filter assembly providesseparate parallel first and second air flow paths, the first air flowpath extending through the first portion of the filter surface and thechamber, and the second air flow path extending through a second portionof the filter surface that is not covered by the chamber and notextending through the chamber.
 2. The vacuum cleaner filter assembly ofclaim 1, wherein the deodorizer comprises at least one deodorizerpellet.
 3. The vacuum cleaner filter assembly of claim 2, wherein thefilter frame is rectangular and the one or more frame side wallscomprise first and second frame side walls spaced from each other by afilter frame width, and first and second frame end walls joining thefirst and second frame side walls and spaced from each other by a filterframe length.
 4. The vacuum cleaner filter assembly of claim 3, whereinthe first and second frame side walls are straight, and the first andsecond frame end walls are straight.
 5. The vacuum cleaner filterassembly of claim 2, wherein the filter comprises a planar filter. 6.The vacuum cleaner filter assembly of claim 2, wherein at least aportion of the filter comprises a plurality of pleats.
 7. The vacuumcleaner filter assembly of claim 6, wherein the second portion of thefilter surface is pleated.
 8. The vacuum cleaner filter assembly ofclaim 2, wherein the filter has a filter width and a filter length, andthe filter-facing portion extends across the entire filter width andonly a portion of the filter length.
 9. The vacuum cleaner filterassembly of claim 8, wherein the filter-facing portion is rectangular.10. The vacuum cleaner filter assembly of claim 2, wherein the frameside walls form a generally planar filter inlet side and a generallyplanar filter outlet side, and the chamber extends from the generallyplanar filter outlet side.
 11. The vacuum cleaner filter assembly ofclaim 2, wherein the portion of the chamber not facing the filtercomprises an opening facing perpendicular to a plane defined by the oneor more frame side walls.
 12. The vacuum cleaner filter assembly ofclaim 2, wherein the frame side walls form a three-dimensional volumehaving a frame length, a frame width, and a frame depth, and the filterextends along the entire frame length and the entire frame width and iscontained within the frame depth.
 13. The vacuum cleaner filter assemblyof claim 12, wherein the chamber is located adjacent and outside thethree-dimensional volume.
 14. The vacuum cleaner filter assembly ofclaim 2, wherein the at least one deodorizer pellet comprises sodiumbicarbonate.
 15. The vacuum cleaner filter assembly of claim 2, whereinthe at least one deodorizer pellet comprises a plurality of deodorizerpellets.
 16. The vacuum cleaner filter assembly of claim 15, wherein theplurality of deodorizer pellets comprise spheres or tablets.
 17. Thevacuum cleaner filter assembly of claim 2, wherein the filter assemblyis adapted to filter all of a total air flow passing through it, anddeodorize only a portion of the total air flow passing through it.
 18. Avacuum cleaner filter assembly comprising: a rectangular filter framehaving first and second frame side walls spaced from each other by afilter frame width, and first and second frame end walls joining thefirst and second frame side walls and spaced from each other by a filterframe length; a filter mounted in the filter frame and extending betweenthe first and second frame side walls, the filter having a filtersurface through which air can pass during use, at least a portion of thefilter comprising a plurality of pleats; a pellet chamber adjacent to afirst portion of the filter surface and not extending outside aperimeter outline defined by the filter frame, the pellet chamber havinga first chamber side wall adjacent and connected to the first frame sidewall, and a second chamber side wall adjacent and connected to thesecond frame side wall, the pellet chamber having a rectangularfilter-facing portion facing the first portion of the filter surface,and defining a passage from the filter-facing portion to a portion ofthe pellet chamber not facing the filter; a plurality of discretedeodorizer pellets contained in the pellet chamber, the deodorizerpellets comprising at least an odor neutralizing substance; wherein thefilter assembly provides separate parallel first and second air flowpaths, the first air flow path extending through the first portion ofthe filter surface and the pellet chamber, and the second air flow pathextending through a second portion of the filter surface that is notcovered by the pellet chamber and not extending through the pelletchamber; wherein the entire filter assembly is connected as a singlereplaceable operative unit; and wherein the filter assembly is adaptedto filter all of a total air flow passing through it, and deodorize onlya portion of the total air flow passing through it.
 19. A vacuum cleanerfilter assembly comprising: a filter frame having a plurality of framemembers, including two side frame members and two end frame members, thefilter frame defining an outer boundary of an air passage through whichair can pass during use; at least one air-permeable filter mounted tothe filter frame, the at least one filter extending between the framemembers across substantially the entire air passage, at least a portionof the at least one filter being pleated; an air permeable chamberextending an entire distance between the two side frame members andattached to the two side frame members, and extending only a portion ofa distance between the two end frame members, the air permeable chamberhaving a filter-facing portion; at least an effective amount ofdeodorizer contained in the air permeable chamber; wherein the filterassembly provides separate first and second air flow paths, the firstair flow path extending through a first portion of the at least onefilter and through the air permeable chamber, and the second air flowpath extending through a second portion of the at least one filter thatis not covered by the air permeable chamber.
 20. The vacuum cleanerfilter assembly of claim 19, wherein the deodorizer comprises aplurality of deodorizer pellets.